package r2118d1119.demo;

import java.util.ArrayList;
import java.util.Collection;

public class DemoCollection {
    public static void main(String[] args) {
        Collection coll = new ArrayList();
        coll.add(10);
        coll.add(20);
        coll.add("hello");
        Student s1 = new Student("zhangsan","01");
        Student s2 = new Student("lisi","02");
        coll.add(s1);
        coll.add(s2);

        System.out.println(coll.toString());
        System.out.println(coll.size());


    }
}
